starknet_chainId - Get Starknet Chain ID
Returns the currently configured Starknet chain ID as a felt252 hex value. Used for network identification, transaction signing, and multi-chain routing.
Starknet RPC endpoint: endpoint URLs, plans and pricing.
Returns the currently configured Starknet chain ID as a hex-encoded felt252 value. This method is used to verify which Starknet network a node is connected to before signing transactions or deploying contracts.
Overview
Starknet chain IDs are encoded as felt252 values representing short ASCII strings. Unlike EVM chains that use numeric IDs, Starknet encodes human-readable network names into their felt representation. This is consistent with Starknet's use of felt252 as the fundamental data type in the Cairo language and the StarkNet OS.
Known Starknet Chain IDs
| Network | Chain ID (ASCII) | Chain ID (Hex felt252) |
|---|---|---|
| Mainnet | SN_MAIN | 0x534e5f4d41494e |
| Sepolia Testnet | SN_SEPOLIA | 0x534e5f5345504f4c4941 |
The hex values are the ASCII byte representations of the network name strings.
{
"jsonrpc": "2.0",
"method": "starknet_chainId",
"params": [],
"id": 1
}Examples
Use Cases
- Network Verification - Confirm you are connected to mainnet or testnet before signing transactions with an Account contract
- Multi-Network Applications - Route requests to the correct network handler based on chain ID
- Transaction Signing - Include the correct chain ID in transaction signatures to prevent cross-network replays
- Wallet Integrations - Display the connected Starknet network in wallet UIs
- Deployment Pipelines - Gate contract deployments on the correct target network
Related Methods
- starknet_specVersion - Get the supported Starknet JSON-RPC spec version
- starknet_syncing - Check node synchronization status
- starknet_blockNumber - Get the latest block number
- starknet_blockHashAndNumber - Get latest block hash and number